This is tough, I am sure. You can attempt to deal with these things in a couple of different ways. When in a situation that you aren't comfortable with, plead a sudden headache and excuse yourself. Do your best to remove yourself from negativity. Develop coping strategies when talking to liars - look them in the eye, don't say anything, but let their subconscious know that you know what they are up to.
When warning loved ones, do it in the form of a question. In other words, let them come to the conclusion that you want them to. When walking into a building that is full of bad energy, turn around, plead the headache or whatever and don't go in there again. You can even say... "I don't know what it is, but every time I go in there I get a really bad headache."
One of the most important things you can do is to reach out to people who have similar problems. I wrote an article for another site which has some suggestions: https://psychicelements.com/blog/psychic-experienc...